[cmake-developers] [CMake 0015602]: Multiple configure_file calls with same input file cause Ninja to output spurious warning

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://public.kitware.com/Bug/view.php?id=15602 
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Reported By:                arlbranch
Assigned To:                
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Project:                    CMake
Issue ID:                   15602
Category:                   CMake
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
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Date Submitted:             2015-06-03 12:01 EDT
Last Modified:              2015-06-03 12:01 EDT
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Summary:                    Multiple configure_file calls with same input file
cause Ninja to output spurious warning
Description: 
Multiple calls to configure_file with the same input file but from different
CMakeLists.txt files causes ninja to output the following:
warning: multiple rules generate .... builds involving this target will not be
correct; continuing anyway

Complete Example:
=================
[branch at fortuna on /dev/pts/2] 611 ~/tmp/cftest
$ cmake --version
cmake version 3.2.3

CMake suite maintained and supported by Kitware (kitware.com/cmake).
[branch at fortuna on /dev/pts/2] 612 ~/tmp/cftest
$ ls -R
.:
cftest.json  CMakeLists.txt  sub/

./sub:
CMakeLists.txt
[branch at fortuna on /dev/pts/2] 613 ~/tmp/cftest
$ cat CMakeLists.txt 
cmake_minimum_required(VERSION 3.2)
project(cftest)

configure_file(cftest.json cftest1.json COPYONLY)
add_subdirectory(sub)

[branch at fortuna on /dev/pts/2] 614 ~/tmp/cftest
$ cat sub/CMakeLists.txt 
configure_file(../cftest.json cftest2.json COPYONLY)

[branch at fortuna on /dev/pts/2] 615 ~/tmp/cftest
$ mkdir ../cfbuild && cd ../cfbuild
[branch at fortuna on /dev/pts/2] 616 ~/tmp/cfbuild
$ cmake -G Ninja ../cftest
-- The C compiler identification is GNU 5.1.0
-- The CXX compiler identification is GNU 5.1.0
-- Check for working C compiler using: Ninja
-- Check for working C compiler using: Ninja -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler using: Ninja
-- Check for working CXX compiler using: Ninja -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /home/branch/tmp/cfbuild
[branch at fortuna on /dev/pts/2] 617 ~/tmp/cfbuild
$ ninja
ninja: warning: multiple rules generate /home/branch/tmp/cftest/cftest.json.
builds involving this target will not be correct; continuing anyway
ninja: no work to do. 


Steps to Reproduce: 
1) Create the project in the Description
2) Configure with the Ninja generator
3) build with ninja
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Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2015-06-03 12:01 arlbranch      New Issue                                    
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